The present invention comprises a new and distinct variety of pelargonium, botanically known as Pelargonium zonale and hereinafter referred to by the variety name ‘KLEPZ15403’. ‘KLEPZ15403’ originated from a cross-combination in June 2010 in Stuttgart, Germany between the female pelargonium variety ‘PZ-2006-0158’ (unpatented) and the proprietary male pelargonium variety ‘PZ-2007-0004’ (unpatented).
Seeds from the cross-combination in June 2010 in Stuttgart, Germany were obtained. The seeds were sown and plants were grown for evaluation. A single plant was selected in June 2011 and subsequently named ‘KLEPZ15403’. In September 2011 ‘KLEPZ15403’ was first vegetatively propagated in Stuttgart, Germany by vegetative cuttings from stems. ‘KLEPZ15403’ was found to reproduce true to type in successive generations of asexual propagation via vegetative cuttings in Stuttgart, Germany.